The present invention relates to a catalyst for producing a living olefin polymer, a process for producing the polymer, and a process for producing a telechelic olefin polymer.
Crystalline polyolefins such as polyethylene and isotactic polypropylene are superior in mechanical physical properties and utilized widely in structural materials such as automobile parts requiring high strength. On the other hand, polyolefins are hydrocarbon macromolecules which are hardly compatible with materials having polar groups, such as coatings and dyestuffs. To render polyolefins readily compatible with these materials and more functional, functional groups may be added to the polyolefin molecules.
Aiming at a highly functional polyolefin, there has been an attempt to attach a functional group to the polyolefin by synthesizing a highly chemically reactive living polyolefin having catalytically active species bound to its polymer terminals, and chemically modifying the polyolefin with a functional group attaching compound by utilizing the reactivity of these polymer terminals.
For example, as shown in xe2x80x9cKobunshi (High Polymers)xe2x80x9d, Vol. 44, pp. 436-440, July issue (1995), xe2x80x9cGosei Jyushi (Plastics)xe2x80x9d, Vol. 42, pp. 32-35, April issue (1996) etc., it is known that one terminal of living polypropylene synthesized with a catalyst consisting of a vanadium acetyl acetonate complex and an organoaluminum compound is modified to provide the terminal with iodine, an amino group, aldehyde group, vinyl group, phenyl group, methacrylate group, trimethylsiloxy group, glycidyl group, carboxylic acid chloride etc.
In the processes described above, however, it is not possible to introduce a functional group into the other terminal of living polypropylene as the terminal for growth initiation, so there is a limit to a higher functionalization of polypropylene.
The object of the present invention is to provide a catalyst for producing a living olefin polymer which enables one to produce a telechelic olefin polymer in which all the terminals of polyolefin polymer chains have been modified with arbitrary functional groups, a process for producing the polymer, and a process for producing a telechelic olefin polymer.
As a result of their eager study, the present inventors found that a catalyst having a plurality of living polymerization active sites is obtained by reacting a living polymerization catalyst for olefins one after another with a compound having a plurality of carbon-carbon double bonds in the molecule, then a living polymer having active sites at all the terminals of its polymer chain: is formed by using this catalyst for living polymerization of olefins, and these active sites are converted by modification into arbitrary functional groups, whereby all the terminals of its polymer chain can be provided with the functional groups. The present invention was thereby completed.
That is, the essence of the present invention lies in a catalyst for producing living olefin polymers, obtained by contacting a catalyst having the ability to cause ethylene and/or olefins (excluding ethylene) to undergo living coordination polymerization, with a compound having a plurality of intramolecular carbon-carbon double bonds.
Further, the catalyst for producing living olefin polymers according to the present invention is characterized in that the olefins are xcex1-olefins of 3 to 8 carbon atoms.
In addition, the catalyst for producing living olefin polymers according to the present invention is characterized in that the catalyst having the ability to cause living coordination polymerization comprises a vanadium compound represented by the general formula I: 
(wherein R1 to R3 represent a hydrogen atom or a hydrocarbon group of 1 to 8 carbon atoms provided that at least one of R1 to R3 is a hydrogen atom but not all R1 to R3 are hydrogen atoms) and an organoaluminum compound represented by the general formula RnAlX3xe2x88x92n (wherein R represents an alkyl group of 1 to 18 carbon atoms or an aryl group, X represents a halogen atom or a hydrogen atom, and n is an arbitrary real number in the range of 1xe2x89xa6n less than 3).
Furthermore, the catalyst for producing living olefin polymers according to the present invention is characterized in that the compound having a plurality of intramolecular carbon-carbon double bonds is an xcex1,xcfx89-unconjugated diene of 5 to 14 carbon atoms.
Moreover, the catalyst for producing living olefin polymers according to the present invention is characterized by being obtained by contacting the catalyst having the ability to cause living coordination polymerization with the compound having a plurality of intramolecular carbon-carbon double bonds, in the presence of olefins not polymerized by the catalyst having the ability to cause living coordination polymerization.
In addition, the catalyst for producing living olefin polymers according to the present invention is characterized in that the olefins not polymerized by the catalyst having the ability to cause living coordination polymerization are cycloolefins or internal olefins or olefins substituted at the 2-position.
Further, the essence of the present invention lies in a process for producing living olefin polymers, comprising homopolymerization or copolymerization of ethylene and/or olefins (excluding ethylene) in the presence of the catalyst for producing living olefin polymers described above.
Furthermore, the process for producing living olefin polymers according to the present invention is characterized in that the olefins are xcex1-olefins of 3 to 8 carbon atoms.
Moreover, the process for producing living olefin polymers according to the present invention is characterized by homopolymerization of propylene or copolymerization thereof with ethylene.
Finally, the essence of the present invention lies in a process for producing telechelic olefin polymers, comprising chemical modification of the terminals of living olefin polymers produced by the process described above.